The invention relates to improving security and access control for doors using a merged power-communication cable, which allows the entire access control identification mechanism to reside within the door.
Today, an access control system for a door requires at least an access control identification mechanism, an access controlled door lock, a way to generate a Request-to-Exit (REX) signal, and a door position sensor. These elements are used to form the prior art access control system involving a power network and a data-communications network. An equipment closet is usually physically located near the door being controlled. The equipment closet contains a door lock power supply and a data-communications node. The power network couples to the door lock power supply. The data-communications network couples to the data-communications node. The data-communications node communicates with a central security node, often through a communications network.
There are several problems with the access control door systems of the prior art. Installing an access controlled door lock system involves a lot of wiring, entailing high installation expenses. The power network and the data-communications networks require many different cables wired to each door being controlled. Once the wiring has been installed, each interface from the equipment closet to the door must be tested. Such testing costs personnel time and may cause delays in deploying an access control system in multiple door environments, such as industrial, commercial and government buildings. Additionally, maintenance and repair is complicated by the wiring complexity. These complications cost the user money.
Some common terms used to describe communications follow, based upon on the web site glossary of technical terms from the web site http://www.its.bldrdoc.gov/fs-1037/dir-001/—0063.htm, accessed in 2004.
The Open Systems Interconnection-Reference Model (OSI-RM) refers to an abstract description of the digital communications between application processes running in distinct systems. The model employs a hierarchical structure of seven layers. Each layer performs value-added service at the request of the adjacent higher layer and, in turn, requests more basic services from the adjacent lower layer:
The Physical Layer is Layer 1, the lowest of seven hierarchical layers of the OSI-RM. The Physical layer performs services requested by the Data Link Layer. There are three major functions and services performed by the physical layer. First, establishment and termination of a connection to a communications medium. Second, participation in the process whereby the communication resources are effectively shared among multiple users, e.g., contention resolution and flow control. And third, conversion between the representation of digital data in user equipment and the corresponding signals transmitted over a communications channel.
The Data Link Layer is Layer 2 of the OSI-RM. This layer responds to service requests from the Network Layer and issues service requests to the Physical Layer. The Data Link Layer provides the functional and procedural means to transfer data between network entities and to detect and possibly correct errors that may occur in the Physical Layer. Note: Examples of data link protocols are HDLC and ADCCP for point-to-point or packet-switched networks and LLC for local area networks.
The Network Layer is Layer 3 of the OSI-RM. This layer responds to service requests from the Transport Layer and issues service requests to the Data Link Layer. The Network Layer provides the functional and procedural means of transferring variable length data sequences from a source to a destination via one or more networks while maintaining the quality of service requested by the Transport Layer. The Network Layer performs network routing, flow control, segmentation/desegmentation, and error control functions.
The Transport Layer is Layer 4 of the OSI-RM. This layer responds to service requests from the Session Layer and issues service requests to the Network Layer. The purpose of the Transport Layer is to provide transparent transfer of data between end users, thus relieving the upper layers from any concern with providing reliable and cost-effective data transfer.
The Session Layer is Layer 5 of the OSI-RM. This layer responds to service requests from the Presentation Layer and issues service requests to the Transport Layer. The Session Layer provides the mechanism for managing the dialogue between end-user application processes. It provides for either duplex or half-duplex operation and establishes checkpointing, adjournment, termination, and restart procedures.
The Presentation Layer is Layer 6 of the OSI-RM. This layer responds to service requests from the Application Layer and issues service requests to the Session Layer. The Presentation Layer relieves the Application Layer of concern regarding syntactical differences in data representation within the end-user systems. Note: An example of a presentation service would be the conversion of an EBCDIC-coded text file to an ASCII-coded file.
The Application Layer is Layer 7, the highest layer of the OSI-RM. This layer interfaces directly to and performs common application services for the application processes; it also issues requests to the Presentation Layer. The common application services provide semantic conversion between associated application processes. Note: Examples of common application services of general interest include the virtual file, virtual terminal, and job transfer and manipulation protocols.
Communications refers herein to at least one of the following First, information transfer, among users or processes, according to agreed conventions. Second, the branch of technology concerned with the representation, transfer, interpretation, and processing of data among persons, places, and machines. The meaning assigned to the data typically must be preserved during these operations.
Information transfer refers herein to the process of moving messages containing user information from a source to a sink.
Data refers here to representations of facts, concepts, or instructions in a formalized manner suitable for communication, interpretation, or processing by humans or by automatic means. Any representations such as characters or analog quantities to which meaning is or might be assigned.
A Layer in a telecommunications network and/or an open systems architecture, refers herein to a group of related functions that are performed in a given level in a hierarchy of groups of related functions. In specifying the functions for a given layer, the assumption is made that the specified functions for the layers below are performed, except for the lowest layer.
Open systems architecture refers herein to a layered hierarchical structure, configuration, or model of a communications or distributed data processing system and/or a nonproprietary systems architecture.
The layered hierarchical structure, configuration, or model of a communications or distributed data processing system provides the following: the layered hierarchical structure enables system description, design, development, installation, operation, improvement, and maintenance to be performed at a given layer or layers in the hierarchical structure. The layered hierarchical structure allows each layer to provide a set of accessible functions that can be controlled and used by the functions in the layer above it. The layered hierarchical structure enables each layer to be implemented without affecting the implementation of other layers. The layered hierarchical structure allows the alteration of system performance by the modification of one or more layers without altering the existing equipment, procedures, and protocols at the remaining layers.
Examples of independent alterations by modifying one or more layers include the following. Converting from wire to optical fibers at a physical layer without affecting the data-link layer or the network layer except to provide more traffic capacity. And altering the operational protocols at the network level without altering the physical layer.
Connection refers here to at least one of the following: A provision for a signal to propagate from one point to another, such as from one circuit, line, subassembly, or component to another. An association established between functional units for conveying information.
Communications medium refers herein to at least one of the following: In telecommunications, the transmission path along which a signal propagates, such as a wire pair, coaxial cable, waveguide, optical fiber, or radio path. The material on which data are or may be recorded, such as plain paper, paper tapes, punched cards, magnetic tapes, magnetic disks, or optical disks.
A channel refers herein to at least one of the following: A connection between initiating and terminating nodes of a circuit. A single path provided by a transmission medium via either physical separation, such as by multipair cable or electrical separation, such as by frequency- or time-division multiplexing. A path for conveying electrical or electromagnetic signals, usually distinguished from other parallel paths. Used in conjunction with a predetermined letter, number, or codeword to reference a specific radio frequency. The portion of a storage medium, such as a track or a band, that is accessible to a given reading or writing station or head. In a communications system, the part that connects a data source to a data sink.
A transfer refers herein to sending information from one location and to receive it at another.
A packet refers herein to a sequence of binary digits, which may including data and/or control signals, that is transmitted and/or switched as a composite whole. The data, control signals, and possibly error control information, are typically arranged in a specific format.
A format refers herein to the arrangement of bits or characters within a group, such as a word, message, or language.
A group refers herein to the following within the context of frequency division multiplexing and/or in the context of a set of characters forming a unit for transmission of cryptographic treatment. A group in frequency-division multiplexing refers herein to a specific number of associated voice channels and/or data channels, either within a supergroup or as an independent entity.
Routing refers herein to the process of determining and prescribing the path or method to be used for establishing telephone connections or forwarding messages.
TCP/IP refers herein to Transmission Control Protocol/Internet Protocol, which is a set of communications protocols required to communicate over a channel with the Internet. A TCP/IP Stack refers herein to the method of interacting with the Internet, which is often implemented as software running on a computer. The Internet Protocol refers herein to a packet switching protocol used as the network layer in the TCP/IP stack.
To summarize. Methods and apparatus are needed which simplify installation of access control systems for doors. A simple, modular approach is needed for installing and operating an access control system for a door. Access control systems are needed which can be installed in a door with a minimum of wiring. Access control systems are needed which interact across standard communications networks with centralized security systems.